Improvement in piston-packing



N. PETERS. PHOTD-LITNOGRAPHER, WASHINGTON D C ORLANDOKELSEY, or WORCESTER,- MAssAcnUsETTs Letters-Patent No; 103,34 3, date1l May 24, 1870.

IMPnovBMn'NrIN PIsTQNAcKING.

TheSchedule` referredtp these Letters Patent and making part of thesame.

fMassachnsettahave invented certain Improvements in th'e` Pistons of Steam-Engines, of which the following is aspeciiication.`

My invention relates to the arrangementand construction of bearing and packing-rings of a steamp'acked piston, andfin the form ot'a cylindrical shell `for supporting the same; and also in a device for regnlatingthe amount of pressurewithin the piston.

.To enable others skilled-lin .the artto make and use my invention,-`I wiltnow proceed to vdescribe its constructionand operation,

Figure l is a section through the piston.` Figure l2 shows another.arrangement of' packingl fringe.`

"Figure 3 an irnd; view ofthe piston. VFigures 4 and5vare variations in lthe construction 4 ofthe pressureLadjnstment. l i

Figuref` shows the modeof tonguing therings. Referringto fig.` V

l A isthe body ofthe piston.

. 0', the spider, cast to the .bodvofi'pistoin and towhich the follower is generally bolted. l

' .Df is a cyIindiiCaIshelI, fitting upon the spider', and

l having upon it the rihs'd, turned .to the-diameter of -the cylinder. i i

The shell Dis inadein.. one pieceor divided centrally, as shown in iig. 1, for.greatereonvenienceof putting on the ringorringslorscgments E.

By thus dividing 'the' shell D, as`- shown, laterally? between the ilangesxdf, the supporting-ringer rings E may be pnt in place withoutstraining,ior the risk of breaking, incidental lto a4 solidshell; and, also, the

" rings H may be pnt on 4inthe same manner without springing, by using the iianges d'ras-a snpporton one side, and the piston ortblloweron the other.` The advantageof this will be understood when we l consider that the springing of the rings is certain to alter and destroy their circular form, and they can never l i itvthe cylinder as accurately as when' turned 'to 'the i proper size and adjusted, without springing. i These,

as theyibeeome worn, are set out by the set-screws g,

l so as tofcenter the pistomand keepA it moderately tight, even wheuno steam is admitted.

`These lings E are held `in position and prevented from crowding upon the 'expansion-rings H by the idangesd,or an equivalent'-V device. H H are expansible rings, fitted between the flanges diand, the pistonhead, on one side, and the follower 4on the other. t

There is suiiicientspace between them and shell D to permit the free circulationof the steam `which is admitted through the shelllby holes h.

Both the centering-ringsand the packing-rings are .tongued and lapped, soas to prevent" the steam from they nearly join each other with an upward deflection,

beneaththe valve M.

Holes u are drilled throughthe piston-head and fol-v lower, so as to connect passages KS with the exterior of the piston.

' By thus connecting the exhaust and the steam end of the cylinder 'beneath the valve M, I obtaina mean pressure between the t\vo,;so that valve M only opens when the pressure is less in the piston than beneath the valve. Y

By thus reducing the pressure within the piston, the packing-ringswill not bind so hard 'againstthe cylinder, andthe piston will work muchv easier under a `great head of steam, as in the caseof a' locomo-` tive going up grade, with full pressure of steam and slow speed. Y

This object 4may be partially accomplished when the two ports KT K are connected by a chamber, as in fig. 4, in which case more steam would pass from the steam to the exhaust side.

In certain conditions, where the valve Vis likely to he `clogged with sediment, it maybe dispensed witll, asin iig. 5, with nearly as good a result.

What I claim as my invention, and desire to secure 4,by Let-ters Patent, is-

1. The cylindrical 'shell D, having flanges for the support of the bearing-rings E or packing-rings H, and divided laterally'between the flanges, for the purpose hereindescribed.- v

l 2; The cylindrical shell D,divided laterally and constrncted as shown, with openings a for the passage oi' steam, in combination with -an adjustable supportingring,",E, and packing-rings H, as herein described.

, 3. The steam-ways K' K', connectingtheste'am and exhaust ends of the cylinder with the interior of th e purpose herein described. 'ORLANDO KELSEY.

piston, either with or Without the valve M, for the v Witnesses:

EDWD. BROWN, Jos. BABY. 

